Turkish President Recep Tayyip Erdogan on Monday called for the lifting of US sanctions blocking some defense purchases by Turkey and the repeal of other “unilateral” measures that sully trade between the two countries.

The president made the comments while speaking to a group of Turkish and American businesspeople during a visit to New York for the UN General Assembly (UNGA), and came shortly after reports emerged in Greek media that Turkey could transfer its Russian-made S-400 missile defense system to Incirlik Air Base as part of a pathway to reentry into the F-35 jet program.

Relations have been strained between the two NATO allies in recent years over political rifts regarding the Eastern Mediterranean, Gaza, Syria and Turkey’s purchase of the S-400 systems, which led to US sanctions and Ankara’s removal from the F-35 program in 2019.

Struggling to modernize its air force, Turkey then looked to buy 40 Block-70 F-16 fighter jets and 79 modernization kits from Washington, but that deal was long delayed. The $23 billion deal was only signed in June after Turkey endorsed Sweden’s bid to join NATO, a de facto quid pro quo that led to a thaw in relations. Sweden’s bid to join the alliance, which emerged in light of Russia’s February 2022 full-scale invasion of Ukraine, had been delayed for over 18 months due to Ankara’s hesitance.